Derzsy’s disease and Muscovy duck parvovirus disease have become common diseases in waterfowl culture in the world and their potential to cause harm has risen. The causative agents are goose parvovirus (GPV) and Muscovy duck parvovirus (MDPV), which can provoke similar clinical symptoms and high mortality and morbidity rates. In recent years, duck short beak and dwarfism syndrome has been prevalent in the Cherry Valley duck population in eastern China. It is characterised by the physical signs for which it is named. Although the mortality rate is low, it causes stunting and weight loss, which have caused serious economic losses to the waterfowl industry. The virus that causes this disease was named novel goose parvovirus (NGPV). This article summarises the latest research on the genetic relationships of the three parvoviruses, and reviews the aetiology, epidemiology, and necropsy characteristics in infected ducks, in order to facilitate further study.

The study of histopathological changes caused by influenza A (H5N8) viral infection in bird species is essential for the understanding of their role in the spread of this highly infectious virus. However, there are few such studies under natural conditions in minor gallinaceous species. This article describes the pathomorphological findings in Colchis pheasants infected naturally with H5N8 during an epizootic outbreak in Bulgaria. Samples of internal organs of 10 carcasses were collected for histopathological and immunohistochemical evaluation, virus isolation and identification, and nucleic acid detection. Consistent macroscopic findings were lesions affecting the intestine, heart, lung, and pancreas. Congestion and mononuclear infiltrate were common findings in the small intestine, as were necrosis and lymphoid clusters in the lamina propria of the caeca. Congestion with small focal necrosis and gliosis with multifocal nonpurulent encephalitis were observed in the brain. Myocardial interstitial oedema and degenerative necrobiotic processes were also detected. Immunohistological analysis confirmed systemic infection and revealed influenza virus nucleoprotein in all analysed organs. Variable necrosis was observed in the brain, liver, trachea, heart, small intestine, and caeca. Viral antigen was commonly found in the brain, heart, lung and trachea. Contact with migrating waterfowls was suspected as a reason for the outbreak.

Introduction: Laryngeal swab samples collected from three waterfowl slaughterhouses in central Taiwan were cultured and suspected isolates of Riemerella anatipestifer were identified by API 20NE and 16S rDNA PCR. Material and Methods: Serum agglutination was used for serotyping, and antimicrobial susceptibility was tested. Results: Seventy-six R. anatipestifer isolates were detected, and the prevalences in the ducks and geese were 12.3% (46/375) and 8.0% (30/375), respectively. The positive isolation rates were 65.6% for all arriving waterfowl, 76.0% for birds in the holding area, 1.6% for defeathered carcasses, but zero for degummed carcasses. A PCR examination detected R. anatipestifer in the slaughtering area frequently. Serotype B was dominant in both duck (34.8%) and goose (46.7%) isolates, but the wide serotype distribution may very well impede vaccination development. All isolates were resistant to colistin, and 79.7% were resistant to more than three common antibiotics. Conclusion: The results proved that most ducks had encountered antibiotic-resistant R. anatipestifer in rearing, which suggests that the bacterium circulates in asymptomatic waterfowl. It is worth noting that most waterfowl farms were found to harbour R. anatipestifer, and contaminated slaughterhouses are a major risk factor in its spread. Effective prevention and containment measures should be established there to interrupt the transmission chain of R. anatipestifer.

Viral infections are the greatest threat to waterfowl and cause significant economic losses. Diagnosis and differentiation of three goose viruses is difficult in the field and often requires laboratory confirmation. Therefore, the aim of the study was to develop a triplex PCR and optimise its parameters for simultaneous detection of DNA of goose parvovirus (GPV), goose polyomavirus (GHPV), and goose circovirus (GoCV). The DNA of viruses isolated from field cases from the National Veterinary Research Institute’s own collection was used for the study. The primer attachment temperature, the number of reaction cycles, and the Taq DNA polymerase and Mg²⁺ concentrations were optimised. The sensitivity and specificity of this triplex PCR was also determined. Based on the obtained results, triplex PCR parameters were optimised for simultaneous detection of DNA of GPV, GHPV, and GoCV in one sample. The following PCR products of the expected size were obtained: GPV DNA of 806 bp, GoCV DNA of 571 bp, and GHPV DNA of 180 bp. The developed triplex PCR method proved to be useful for simultaneous detection of infections with three waterfowl viruses and will be used in relevant laboratory diagnostics.

Forty-seven Newcastle disease virus (NDV) strains isolated from fecal samples of waterfowls in Alaska and Siberia from 1991 to 1996 were analyzed for their virulence. None of the viruses formed plaques on MDBK cells in the absence of trypsin. Of these, 29 strains showed virulent character by the mean death time with the minimum lethal dose in chicken embryos comparable to velogenic NDV strains. Of the 29 strains, 11 were sequenced for their fusion protein (F) gene. The results showed that 5 of them contained a pair of dibasic amino acids at the cleavage site of the F, which is of a virulent type. The present results suggest that potentially virulent strains of NDV are maintained in migratory waterfowl populations in nature, and that some of those may be transmitted to domestic poultry and acquire pathogenicity during passages in chicken population

Development of scientifically based activities for rehabilitation of waterfowl (ducks) against helminthoses on the territory of the Republic of Belarus was realized. In course of the study there were analyzed fauna of helminthes and revelation of the main ways of their circulation in environment conditions; expansion and species composition of mollusks of Belarusian Poozerye; determination of species composition of metacercaria revealed in mollusks. In course of determination of intermediate and additional hosts of helminth infestation of ducks it was noted that the main carriers of larval stages of helminthes in ducks were the following species of frash-water mollusks: Vivaparus contectus; Vivaparus vivaparus; Galba palustris; Radix ovata; Radix auricularia; Sphaerium subsolidum; Bithynia tentaculata; Planorbis carinatus; Planorbis planorbis; Coretus corneus. In the studied samples there were revealed metacercaria of Echinostoma revolutum; Hypoderaeum conoideum; Cataropis verrucosa; Echinostoma dietsi. Assumption that some representatives of molluscum (Viviparus contectus; Viviparus viviparus; Planorbis planorbis) were the transport hosts for echinostomiasis was not proved.

Research of a pancreas of geese in course of different age-specific periods was realized in the conditions of the Republic of Belarus. Ecological features of water fowl inhabitance, prevalence of phytogenous forages in a diet of led in first two life decades to rapid growth of body weight and pancreas which was capable to adapt an organism to new conditions of existence. The subsequent growth and differentiating processes in a pancreas of geese showed direct correlative dependence on the basic physiological states of their organism (plumage, a moult, puberty, egg production efficiency). By the beginning of egg production (6 months) the basic structural components of secretory parts of gland of geese reached a rather developed condition, but their full morphological and functional maturity occurred by 2-year-old age, possibly, because of a long reproductive period of life. | Проведено исследование поджелудочной железы у гусей в разные возрастные периоды. Экологические особенности среды обитания водоплавающих птиц, преобладание в рационе кормов растительного происхождения приводят в первые две декады жизни к бурному росту массы тела животных и поджелудочной железы, способной адаптировать организм к новым условиям существования. Последующие ростовые и дифференцировочные процессы в поджелудочной железе гусей проявляют прямую коррелятивную зависимость от основных физиологических состояний их организма (оперение, линька, половое созревание, яйценосная продуктивность). К началу яйценоскости (6 месяцев) основные структурные компоненты секреторных отделов железы гусей достигают достаточно развитого состояния, но их полная морфофункциональная зрелость наступает к 2-летнему возрасту животных, вероятно, из-за продолжительного репродуктивного периода жизни.